The celebrity entrepreneur's cosmetic line saw "very strong sales" in its first quarter on shelves, Ulta CEO Mary Dillon said in a call with investors on Thursday.

Kylie Cosmetics drove strong traffic to stores, Dillon said, in a quarter in which Ulta's comparable sales grew 9.4% in the quarter, versus the expected 7.9%. The makeup brand also attracted more diverse and younger shoppers to Ulta locations.

"We were essentially out of stock for a few weeks at the end of the quarter," for certain Kylie Cosmetics products, Dillon said.

Items are now back in stock, and the company has addressed inventory issues, Dillon said. Ulta is also preparing to launch new Kylie Cosmetics products, including eye shadow palettes and more lip products.

Earlier in March, Forbes reported that Kylie Jenner became the world's youngest self-made billionaire, fueled by Kylie Cosmetics' revenue growth of 9%. The growth was fueled by the Ulta partnership, which brought her products to the retailer's more than 1,000 US stores.